| The thesis is chosen and specific studies are carried out according to"the Eleventh Five-year Program"National R & D Project (the Development and Demonstration of Water Resources Real-time Monitoring & Management in middle city groups of Liaoning Province).The Lower River Plain is located in central Liaoning Province, with abundant natural resources and obvious region advantage. The area is an important economic centre around Bohai Sea economic belt and the traditional national industry base. Meanwhile, as the largest alluvial plain of Liaoning Province, it is the most important base of commodity grain in Liaoning Province, playing a very important role. In recent years, with the adjustment and development of domestic economy, the contradiction of industrial use of water has become more and more serious, and the demands of groundwater has been more and more urgent. However, during the development and utilization of groundwater, there occurs a series of problems caused by irrational human activities. For example, the imbalance exploitation intensity and the poor exploitation techniques lead to groundwater cone of depression in Shenyang City and Liaoyang City and the environmental geologic problem of sea water intrusion in coastal cities such as Yingkou City. Therefore, it is a very urgent and necessary task to analyze the circulation characteristics of Quaternary groundwater in Lower River Plain, estimate the renew-ability, rationally evaluate the quantity of groundwater available exploitation, and achieve real-time prediction and forecast of groundwater resources, in order to implement reasonable, efficient and sustainable use of groundwater resources in Lower River Plain.On the basis of the analysis of regional conditions of meteorology, hydrology, geology and hydrogeology, the three-dimensional geological structure model is built with modern theory and techniques, combined with a lot of borehole data, achieving the spatial visualization of groundwater resources information. The lithology and distribution of unconsolidated porous Quaternary aquifer is analyzed by the model, laying a solid foundation for the generalization of aquifers and the analysis of groundwater circulation characteristics.The spatial-time evolutional characteristics of Quaternary porous phreatic water in Lower River Plain are analyzed according to long-time observed data of groundwater level and quality. Further more, the spatial-time variation rule of hydraulic and hydro-chemical indexes are calculated and analyzed from the angle of groundwater dynamics and groundwater chemical dynamics, providing reasonable support for quantitive analysis of groundwater circulation conditions.The hydro-chemical field and hydro-dynamic field are coupled by the associated method of hydrogeochemistry and groundwater dynamics, building the calculation formula for groundwater real velocity (U) and groundwater age (t) expressed by the indexes of hydrogeochemical indexes. Through plotting the chart of groundwater circulation characteristics, the groundwater circulation characteristics are evaluated quantitatively, improving the qualitative evaluation method described by"active","slow"and other qualitative words.The main influencing factors on groundwater renew-ability are analyzed from the three aspects of groundwater recharge conditions, aquifer characteristics and groundwater circulation pattern. The evaluation indexes system for groundwater renew-ability is built, and the groundwater renew-ability is evaluated quantitatively with the method of Fuzzy Comprehensive Assessment and GIS techniques. Some suggestions for groundwater rational development and utilization are given according to the evaluation result. The evaluation result shows that the groundwater renew-ability of west area is greater than the east area, and the alluvial-proluvial fan area is better than plain area. The groundwater renewable area of class"extremely strong"to"strong"is mainly distributed in the alluvial-proluvial fan of Hunhe River, Dalinghe River and Xiaolinghe River, and class"weak"to"extremely weak"mainly in central deposit plain and southern coastal alluvial delta plain. For extremely renewable area of Dalinghe River fan, the groundwater exploitation can be increased properly; but for the area of Xiaolinghe River fan, where has the same groundwater renew-ability but 80%~100%groundwater exploitation extent, and the area of Shenyang City and Liaoyang City, the groundwater exploitation intensity should be adjusted to avoid environmental geological problems. For the area with strong renew-ability but non-longtime supply ability, the groundwater exploitation should maintain current situation, ensuring safe and rational development and utilization. For the area with weak renew-ability but strong storage capacity, the groundwater exploitation can be increased under current situation, efficiently use the storage capacity of aquifer system. For the area of extremely weak renew-ability, it is not suggested exploit large quantity of groundwater, preventing from serious environmental geological problems.However, groundwater renew-ability can only reflect the natural recharge velocity of the area, but can not quantitatively calculate the groundwater available exploitation quantity. Therefore, the real-time groundwater available exploitation evaluation model is built based on water budget theory. With the model and real-time monitoring data of hydrology, meteorology, groundwater dynamic information, the groundwater available exploitation can be calculated and analyzed directly, fast and efficiently. The evaluation result shows the water budget is positive during the year 2004 and 2005, and the total groundwater available exploitation quantity is 3.49 billion in 2004 and 3.29 billion in 2005. The water budget is negative is negative in dry year 2006, and the actual exploitation is 0.84 billion more than available exploitation quantity. The groundwater exploitation potential is great in the area of Dalinghe River Basin, Dongling district and Sujiatun District; there still exists a little groundwater exploitation potential in the area of Haichenghe River Fan, Taizihe River Fan and Hunhe River Fan; the groundwater exploitation potential is medium in the lower reach area of Liaohe River Plain; the groundwater exploitation potential is weak in western and northern area influenced by meteorology; and groundwater exploitation module is less than 200 thousand m3/a?km2 in Shenyang City and Liaoyang City because of serious over-exploitation.Groundwater numerical model of the study area is built based on groundwater seepage theory. Through read, calculation and format transfer of real-time monitoring data by the use of"Real-time Forecast System of Quaternary Groundwater Available Exploitation in Lower River Plain, the real-time data is input into the numerical model and run, achieving fast and efficient real-time forecast of groundwater resources. Once the simulation period and annual source and sinks are determined, the model has solved the problem of repeated input and adjustment of source and sinks during traditional groundwater numerical simulation, saving time for data input, update and model calculation. The simulation result is accurate and visualized, and it is significant for the real-time management and regulation of groundwater resources in Lower Liaoher River Plain.
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